Yurttas/PL/DBL/oracle/F/03/Bank/q04.pc

 1/*  
 2REM
 3REM q04.pc
 4REM
 5REM Suppose we want a relation showing customers and the branches
 6REM from which they borrow, but do not care about the amount of the
 7REM loan, or the loan number.
 8REM
 9*/
10
11#include <stdio.h>
12#include <sqlca.h>
13
14#define UNAME_LEN 32
15#define PWD_LEN   16
16
17VARCHAR username[UNAME_LEN]; /* VARCHAR is an Oracle-supplied struct */
18VARCHAR password[PWD_LEN];   /* varchar can be in lower case also. */
19
20char u_name[UNAME_LEN];
21char pwd[PWD_LEN];
22
23struct {
24  char branchname[16];
25  char customername[16];
26} borrower;
27
28void connect_to_oracle();
29void sql_error();
30
31void main(int argc, char* argv[]) {
32  connect_to_oracle();
33
34  EXEC SQL DECLARE c CURSOR FOR
35    SELECT branchname, customername
36    FROM Borrower;
37
38  EXEC SQL OPEN c;
39
40  EXEC SQL WHENEVER NOT FOUND DO BREAK;
41
42  printf("\nbranchname\tcustomername\n");
43  for(;;) {
44    EXEC SQL FETCH c INTO :borrower;
45    printf("%s\t%s\n", borrower.branchname,
46                       borrower.customername);
47  }
48
49  EXEC SQL CLOSE c;
50
51  EXEC SQL COMMIT WORK RELEASE;
52
53  exit(0);
54}
55
56
57void sql_error(char* msg) {
58  char err_msg[128];
59  int buflen, msglen;
60
61  EXEC SQL WHENEVER SQLERROR CONTINUE;
62
63  printf("%s \n", msg);
64  buflen = sizeof(err_msg);
65  sqlglm(err_msg, &buflen, &msglen);
66  printf("%.*s \n", msglen, err_msg);
67  exit(1);
68}
69
70
71void connect_to_oracle() {
72  /* get your username/passwd from "user_pwd.txt" file */
73
74  FILE *in_file;
75  in_file = fopen("user_pwd.txt", "r");
76  fscanf(in_file, "%s", u_name);
77  fscanf(in_file, "%s", pwd);
78
79  strncpy((char *) username.arr, u_name, UNAME_LEN);
80  username.len = strlen((char *) username.arr);
81
82  strncpy((char *) password.arr, pwd, PWD_LEN);
83  password.len = strlen((char *) password.arr);
84
85  EXEC SQL WHENEVER SQLERROR DO sql_error ("ORACLE error-- ");
86  EXEC SQL CONNECT :username IDENTIFIED BY :password;
87
88  printf("connected to oracle - \n");
89}